1. Field of the Invention
The present invention relates generally to television systems, and specifically, to a method and apparatus for correcting corrupted digital video transport streams using a constant minimum bandwidth allocation, randomized null packet payloads, and/or framing validity technique.
2. Background Information
The advancement of technology has facilitated the development and transmission of digital programming to consumers. One such programming is video on demand (VOD). VOD is a service that is offered by, for example, cable companies which allows customers, for a fee, to order and view movies or other programming at any time, typically by using the consumer's set top box. VOD thus offers flexibility by allowing the user to decide when to watch VOD programs. VOD offers a further advantage of allowing the user to pause the VOD program when the user is interrupted by a telephone call, doorbell, etc.
However, VOD service may occasionally cause reception problems. When a VOD program is selected for download to a client receiver, the video services received and decoded may be obscured by artifacts. The degree of obscuration may be total yielding the program content unwatchable. The problem is most prevalent when only a single session is being supported by the system on an RF channel and virtually guaranteed to occur when that single session has been paused and the customer temporarily tunes away. The problem occurs immediately after channel change to the VOD transport stream.